Horsepower - before RWHP

[SLF360]

A full header system without cats and using either the stock or performance FRP muffler would also yield a HP increase in the 10%+ range (with a big increase in loudness, perhaps objectionable to most).

Some like it loud ! :biggrin :biggrin

I have that combo, and it is nice and quiet , until you open up ! Then it's louder than the Stradale, with a beautiful American muscle note !! :thumbsup

 

[richardhead]

Vented SuperCharger

Richard, why do you say ' a vented' supercharger? the reason I ask is that some res[ectable tuners (like Sean Hyland) have said the s/c needs to be vented if the pulley is changed, and others have said it does not. So as a person pondering changing the pulley perhaps you (and other techs like Mike from Toronto) could weigh in on the reasons for or against using the stock s/c without a vent.

First, my technical experience with vented/non-vented is limited. It is generally focused on experience I've had with regular street driven cars, and primarily on the comments of owners. It seems a non-vented unit, properly spec'd and running lower boost for the street, does not pose an issue when everything is going well. However, with higher boost, higher shaft rpm and a little time on the assembly, seal wear can result in modest leak-by if internal pressure leaks develop into the driven gear assembly. The vented or pressure relief setup is just an added feature to avoid the mess of lubricant getting all over everything before you realize other sealing issues exist. If you attach a venting hose to the venting outlet, with a small clear collection bottle, you can see when these internal issues arise by observing lubricant starting to show itself in the bottle. It just seems to me, a vent system is an added feature providing a sense of security for cleanliness, and advance warning indication of other potential issues.

 

[Shadowman]

First, my technical experience with vented/non-vented is limited. It is generally focused on experience I've had with regular street driven cars, and primarily on the comments of owners. It seems a non-vented unit, properly spec'd and running lower boost for the street, does not pose an issue when everything is going well. However, with higher boost, higher shaft rpm and a little time on the assembly, seal wear can result in modest leak-by if internal pressure leaks develop into the driven gear assembly. The vented or pressure relief setup is just an added feature to avoid the mess of lubricant getting all over everything before you realize other sealing issues exist. If you attach a venting hose to the venting outlet, with a small clear collection bottle, you can see when these internal issues arise by observing lubricant starting to show itself in the bottle. It just seems to me, a vent system is an added feature providing a sense of security for cleanliness, and advance warning indication of other potential issues.

There is no doubt that a catch can of sorts would be interesting however I suspect that if the system is vented then the odds are no oil would come out because by default it rides lower that the breather system.

In any case I am all for a clear case with no issues

Shadowman

 

[STUNTS]

Great informative thread and thanks for all the info. I'm compitent when it comes to the mechanics but by no means a mechanic(let alone a tech). So here is my question in regards to a vented or non-vented sc.

Which system is less problematic? What runs more consistent? and what would you say % wise is the vented versus non-vented? My assumption is non-vented is a larger number than vented?